Drug information (analgesics) This leaflet provides information on painkillers and will answer any questions you have about the treatment. Arthritis Research UK produce and print our booklets entirely from charitable donations.
What is pain? Although everyone understands what we mean by the word pain, it s still difficult to define. Put simply, it s usually a protective mechanism that alerts your brain when damage has occurred. Pain is unpleasant, but it s often shortlived and the reasons for it are usually easy to understand, for example if you ve had a fall or burnt yourself. You may decide to take painkillers to ease the pain until it gets better, and if you have arthritis or a related condition you may want to take them during flare-ups. You can also take them before you exercise to help prevent pain.
Arthritis Research UK What s inside? 2 What are painkillers? 2 Simple non-opioid analgesics Paracetamol Non-steroidal anti-inflammatory drugs (NSAIDs) Aspirin Ibuprofen 5 Compound analgesics Table 2: Common examples of compound analgesics 7 Opioid analgesics Table 3: Common examples of opioid analgesics 11 Which medications can help with inflammatory arthritis? 11 What medications are used in nerve (neuropathic) pain? Amitriptyline Gabapentin and pregabalin 12 What if I have problems with my heart? 12 Where can I get more information? 10 What other drugs can help ease pain? Disease-modifying anti-rheumatic drugs (DMARDs) and biological therapies Steroids 10 Which medications can help with osteoarthritis? 1
What are painkillers? are drugs that help to reduce pain. When we talk about painkillers, we re usually referring to a group of drugs called analgesics. There are three different types of analgesics, as shown in Table 1. Drugs may be available under several different names. Each drug has an approved (or generic) name but manufacturers often give their own brand or trade name to the drug as well. For example, Nurofen and Panadol are brand names for ibuprofen and paracetamol, which are the approved names. The approved name should always be on the pharmacist s label even if a brand name appears on the packaging, but check with your doctor, nurse or pharmacist if you re in any doubt. We ll use the approved names in the sections that follow. You don t need to wait until your pain is severe to use analgesics. Take them as the packet advises or as your doctor suggests. Many people find that analgesics aren t as effective as they could be because they don t take them correctly. You can take analgesics before exercise to help prevent pain. Simple non-opioid analgesics Simple non-opioid analgesics are the most common type of analgesic. The most common of these is paracetamol. Paracetamol Paracetamol is available over the counter and is widely used as a painkiller for mild to moderate pain, for example following a minor injury, and for headaches and muscular pains. Paracetamol will also reduce a fever. It s available in 500 mg tablets or in liquid form for children. It s usually taken in doses of two 500 mg tablets up to four times a day. It s well tolerated with very few side-effects. Some people develop a rash, but this is very rare. At doses higher than 4,000 mg (eight tablets) per day, paracetamol can seriously damage your liver. The number you can buy at any one time is limited because of this risk. Care must be taken if you have liver problems or drink a lot of alcohol. It must also be used in lower doses if you have kidney problems. Be aware that many other products, for example cold and flu medications, contain paracetamol. Paracetamol is well tolerated during pregnancy or breastfeeding as long as it s not taken regularly or in doses of more than 2,000 mg per day. 2
Arthritis Research UK Table 1 Common examples of analgesics Mild Pain level Moderate Severe Type Simple non-opioid analgesics e.g. paracetamol, aspirin, ibuprofen Compound analgesics e.g. co-codamol, co-codaprin, co-dydramol Opioid analgesics e.g. codeine, tramadol, morphine What are they? The most common form of analgesic, also including non-steroidal anti-inflammatory drugs (NSAIDs) A combination of drugs in one tablet, usually including paracetamol, aspirin and codeine The strongest types of painkiller What are they used for? Where do I get them? What are the common side-effects? What else should I know? Mild to moderate pain, for example headaches, injuries and osteoarthritis, or as an addition to stronger painkillers Over the counter at supermarkets and chemists, although some NSAIDs are only available on prescription Paracetamol has few side-effects but high doses can cause liver damage NSAIDs have more side-effects, particularly on the stomach Shouldn t be used at high doses for long-term pain Paracetamol and some NSAIDs are available as suppositories Mild to moderate pain, for example injuries and osteoarthritis, or as an addition to NSAIDs Milder forms are available over the counter, but stronger types are only available on prescription Compounds made from codeine can cause constipation, nausea and loss of concentration Can be used instead of NSAIDs if these can t be taken for any reason Moderate to severe pain caused by osteoarthritis, or as an addition to NSAIDs for severe pain Only available on prescription Nausea and vomiting, constipation, drowsiness and dizziness Can cause more sideeffects compared with non-opioid types 3
Many different NSAIDs are available, so if one doesn t work you can try others. Paracetamol doesn t have an antiinflammatory effect, which means it s less helpful for inflammatory arthritis, such as rheumatoid arthritis, so it s commonly taken in combination with non-steroidal anti-inflammatory drugs (NSAIDs). It s usually the first treatment recommended for easing pain caused by osteoarthritis. Non-steroidal anti-inflammatory drugs (NSAIDs) NSAIDs are a type of simple nonopioid analgesic. They help to reduce inflammation, which reduces pain. They can be used in combination with other simple or compound analgesics, so they can be helpful even when there s not a great deal of inflammation, for example in osteoarthritis. NSAIDs start working within a few hours. The effects of some will only last for a few hours but others are effective all day. Your doctor will help you to find the best formula and dose for you. There are now about 20 different NSAIDs available, the most common being aspirin and ibuprofen. Aspirin Aspirin is widely used as a painkiller for mild to moderate pain. It can reduce fever and has an anti-inflammatory effect. It s available over the counter in 300 mg tablets and is usually taken in doses of 300 600 mg four times a day after food. Aspirin can cause stomach-related side-effects at higher doses. Soluble forms reduce this risk to some extent, as do enteric-coated tablets (which have a coating to make sure the drug isn t absorbed into the body until it reaches the small intestine), but you shouldn t take it if you have indigestion, heartburn or a history of stomach ulcers. It can cause serious bleeding in the digestive system, particularly if you drink alcohol, take the blood-thinning drug warfarin or are over 60. For this reason many doctors will now advise you to take some of the newer NSAIDs such as ibuprofen for pain relief because of the reduced risk of sideeffects. You shouldn t use fish oil if you re taking aspirin because they can interact. Aspirin can also make asthma worse and can cause an allergic reaction that results in rashes and hives. If you experience any of these side-effects you must stop taking aspirin immediately. Children and young people under the age of 16 shouldn t take aspirin. 4
Arthritis Research UK Aspirin is also used in low doses (75 mg daily) to reduce the risk of strokes and heart attacks. This dose doesn t have a pain-relieving effect. If you re on long-term, low-dose aspirin you must be careful about taking other NSAIDs because it increases the risk of stomach bleeding. Ask your doctor s advice if you re unsure. Ibuprofen Ibuprofen is a widely used painkiller and anti-inflammatory. It s available over the counter in doses of 200 400 mg and can be taken up to four times a day after food. You can also use ibuprofen gels and creams, which you rub directly onto the affected area. Stronger and slow-release NSAIDs are available on prescription and can be used for rheumatoid arthritis and other types of inflammatory arthritis. You shouldn t take more than one NSAID at a time. NSAIDs can have serious side-effects and shouldn t be used long-term. Speak to your doctor if you need longer term pain relief. For more information see Arthritis Research UK drug leaflet Non-steroidal anti-inflammatory drugs. Compound analgesics Compound analgesics are made from a combination of two different drugs. The most commonly used drugs in compound analgesics are: paracetamol aspirin codeine dihydrocodeine. These drugs are most commonly used because they cause fewer, less severe side-effects. Some compound analgesics containing low doses of codeine are available over the counter, but other stronger ones are only available on prescription. Ask your doctor s advice if you re pregnant or breastfeeding. Older people may be advised to reduce the maximum dose. Common examples of compound analgesics are listed on the next page (see Table 2). Compound analgesics combine two different drugs. They re used for mild to moderate pain. 5
Table 2 Common examples of compound analgesics Type Co-codamol Co-codaprin Co-dydramol What is it? Codeine (8 mg) and paracetamol (500 mg) Codeine (8 mg) and aspirin (400 mg) Dihydrocodeine (10 mg) and paracetamol (500 mg) What dose can I take? Up to two tablets four times a day Up to two tablets four times a day with food Up to two tablets four times a day Where do I get them? Over the counter or on prescription On prescription On prescription What are the most common side effects? Constipation, nausea, drowsiness and dizziness Constipation, nausea, drowsiness, dizziness, heartburn and indigestion Constipation, nausea, drowsiness and dizziness What else should I know? For more severe pain, combinations of 15 mg/500 mg and 30 mg/500 mg are available For more severe pain, combinations of 20 mg/500 mg and 30 mg/500 mg are available 6
Arthritis Research UK Opioid analgesics Opioid analgesics can be more effective for pain relief than simple non-opioid analgesics, so they re used for moderate to severe pain. Pain is considered to be severe if it s disabling, meaning you have to take more frequent rests or can only walk or move awkwardly. Opioid analgesics can cause more sideeffects than simple analgesics and can lead to dependency and addiction, so they re only available on prescription and you ll be monitored more closely by your doctor. They re only used if other analgesics haven t worked. In many cases they re used for short periods of time or alongside other painkillers when necessary to reduce the risk of side-effects and dependency. All side-effects are more common in older people, so the dose may be reduced. The most common side-effects with opioid painkillers are: nausea and vomiting (some people are more prone to this than others but it often settles with time) constipation drowsiness and dizziness, which is increased when combined with alcohol be careful when driving and using electrical equipment reduced concentration or confusion Opioid analgesics are reserved for moderate to severe pain. reduced ability to breath (respiratory depression) make sure the doctor prescribing the drug knows if you have long-term breathing problems like chronic obstructive pulmonary disease or asthma. If you experience any side-effects, talk to your doctor. Opioid analgesics come in a tablet or patch. Your doctor will advise on which type is best for you depending or the severity of your pain, your age and any other medication that you re taking (see Table 3). 7
Table 3 Common examples of Opioid analgesics Type Codeine and dihydrocodeine Tramadol Buprenorphine What are they? The most widely used weak opioid analgesics Stronger than codeine and dihydrocodeine and may work in a slightly different way A strong opioid analgesic for severe pain but can also be given at a low starting dose when used as a low-dose patch What dose can I take? 30 60 mg up to four times a day 50 100 mg up to four times a day Available in slowrelease patches, which have different strengths and can last a week What are the side-effects? Constipation, nausea, drowsiness and dizziness so are avoided for long-term use whenever possible Fewer side-effects than other opioids, but makes some people feel very fuzzy-headed or confused Constipation, nausea, drowsiness and dizziness avoided for long-term use whenever possible Patches may cause an allergic reaction where they re applied to the skin What else should I know? Available at various strengths and in slowrelease formulas for long-term pain Available in a slow-release formula of 100 200 mg for severe pain Can also be combined with paracetamol, which increases its effectiveness Also comes in a tablet which is placed under the tongue for an immediate painkilling effect 8
Arthritis Research UK Type Fentanyl Morphine Oxycodone Methadone A strong opioid analgesic used for severe, long-term pain A strong opioid analgesic used after surgery and for severe, long-term pain A strong opioid occasionally used for severe pain and cancer pain A long-acting and strong opioid Prescribed as a patch which is applied to the skin every 3 days Available in slowrelease tablets (MST), which are usually taken twice a day Available in a variety of strengths as tablets or as slowrelease tablets Dose varies according to the severity of the pain Can cause constipation, nausea, drowsiness and dizziness Patches may cause an allergic reaction where they re applied to the skin Often causes nausea and vomiting as well as constipation, drowsiness and dizziness Often causes nausea and vomiting, constipation, drowsiness and dizziness Often causes nausea and vomiting, constipation, drowsiness and dizziness Also available in lozenge form for immediate pain relief Also available as a liquid and a suppository, or an injection for very severe pain Less sedating than morphine usually taken twice a day to reduce sideeffects when used long term 9
Depending on what type of arthritis you have, your doctor may prescribe specific drugs for your pain. What other drugs can help ease pain? A number of other drugs that work in different ways to analgesics also help to reduce pain. These include diseasemodifying anti-rheumatic drugs (DMARDs) and steroids. Disease-modifying anti-rheumatic drugs (DMARDs) and biological therapies DMARDs (which include traditional DMARDs, immunosuppressant DMARDs and biological therapies) are only used if you ve been diagnosed with a specific type of arthritis, for example rheumatoid arthritis, and they re only available on prescription. They work by altering the underlying disease rather than treating the symptoms. They re not painkillers, but they ll reduce pain, swelling and stiffness over a period of weeks or months by slowing down the disease and its effects on the joints. It can take months before they take effect, but they re very useful for easing pain once they ve started to work. Steroids Like DMARDs, steroids are only used for certain types of arthritis, including rheumatoid arthritis, lupus and polymyalgia rheumatica (PMR). They help to reduce inflammation, which can ease pain. Steroids can be given in tablet form or as an injection. Steroid injections may be offered to people with osteoarthritis if they have inflammation in their affected joints. Both injections and tablets work very quickly, although they won t cure your condition. Which medications can help with osteoarthritis? If you have osteoarthritis you ll probably experience pain at times, so you should use painkillers when it s interfering with your everyday life. Some people with osteoarthritis will find that the pain is more constant, making day-to-day activities difficult, affecting concentration and disturbing sleep. If your pain affects you in these ways you may need to take combinations of medications. Taking combinations can also often help if you have back or neck pain. 10
Arthritis Research UK Which medications can help with inflammatory arthritis? If you have inflammatory arthritis, such as rheumatoid or psoriatic arthritis, you ll need to take a combination of drugs. NSAIDs are more effective than analgesics in relieving the pain and stiffness of inflammatory arthritis. You may also be prescribed one or more DMARDs such as methotrexate and biological therapies by a rheumatologist. These drugs ease pain, swelling and stiffness, and reduce the risk of longer term damage to the joints. Once the DMARDs start to work you may not need to take analgesics and NSAIDs as often. Other types of arthritis also cause pain but require treatments that are more specific, for example NSAIDs are very effective in gout whereas analgesics aren t. You should speak to your doctor if you re unsure. What medications are used in nerve (neuropathic) pain? Nerve pain can be caused by damage to nerves or nerve endings. This causes the nerves to send pain signals to the spinal cord spontaneously, without needing a specific stimulus, or in response to something that wouldn t normally hurt, such as gentle stroking of the skin. This sometimes happens in complications from diabetes and in some people with sciatica and complex regional pain syndrome (reflex sympathetic dystrophy), as well as rheumatoid arthritis. Pain from nerve damage can be very severe and troublesome, for example the pain that s caused by spinal problems or that follows a bout of shingles. This pain may respond to stronger opioids but occasionally other drugs are used. Drugs used to treat nerve damage can include amitripyline, gabapentin and pregabalin. Amitriptyline Amitriptyline is an antidepressant drug but it also has painkilling and sedative effects. It s used in low doses (5 75 mg) 2 hours before bed for nerve pain and for people who have chronic pain associated with sleep disturbance. The dose is usually capped at 50 mg a day if it s only being used for pain relief. It causes drowsiness and a dry mouth and some people can t tolerate even low doses. You shouldn t take amitriptyline if you have certain forms of glaucoma. Gabapentin and pregabalin Gabapentin and pregabalin are also drugs which can be effective for nerve pain. Like amitriptyline, they may be given in combination with other pain medications in the most troublesome nerve pain conditions. 11
What if I have problems with my heart? If you have a serious heart condition, high blood pressure or uncontrolled high cholesterol, or if you re in severe cardiac failure or have just had a heart attack, your doctor may advise you not to take NSAIDs. This is because there s evidence of a slight but important risk of future cardiovascular problems. This risk must be weighed carefully against the benefit you get from NSAIDs, which may be more effective than simple or compound analgesics if you have inflammatory arthritis. Naproxen is generally felt to be the least harmful NSAID in these circumstances. Coxibs are best avoided if you have cardiovascular disease unless you have a peptic ulcer and can t tolerate NSAIDs combined with a proton pump inhibitor. All NSAIDs, particularly diclofenac and high dose ibuprofen, are associated with a slightly increased risk of developing a stroke. Where can I get more information? Arthritis Research UK is the charity leading the fight against arthritis. We do this by funding high-quality research, providing information and campaigning. We publish over 60 information booklets which help people to understand more about their condition, its treatment, therapies and how to help themselves. For more information on any of the conditions or individual drugs mentioned here, see Arthritis Research UK range of booklets and drug leaflets, or speak to your doctor or rheumatology nurse specialist. If you would like any further information about painkillers, or if you have any concerns about your treatment, you should discuss this with your doctor, rheumatology nurse or pharmacist. Speak to your doctor if you have any questions about painkillers and other drug treatments. 12
Arthritis Research UK Notes Record your information here to help you manage your treatment: What am I taking? When/how often? What dosage (if applicable)? Hospital/clinic address: 13
Get involved! You can help to take the pain away from millions of people in the UK by: volunteering supporting our campaigns taking part in a fundraising event making a donation asking your company to support us buying gifts from our catalogue. To get more actively involved, please call us 0300 790 0400 or email us at enquiries@arthritisresearchuk.org or go to: www.arthritisresearchuk.org A team of people contributed to this booklet. The original text was written by Dr Mike Shipley and consultant in pain medicine Dr John Lee, who have expertise in the subject. It was assessed at draft stage by consultant rheumatologist Prof. Bhaskar Dasgupta, FRP team leader/clinical assistant spines Caroline Evans and consultant rheumatology nurse Diana Finney. An Arthritis Research UK editor revised the text to make it easy to read, and a non-medical panel, including interested societies, checked it for understanding. An Arthritis Research UK medical advisor, Kate Gadsby, is responsible for the content overall. Please note: We have made every effort to ensure that this content is correct at time of publication, but remember that information about drugs may change. This information sheet is for general education only and does not list all the uses and side-effects associated with this drug. For full details please see the drug information leaflet that comes with your medicine. Your doctor will assess your medical circumstances and draw your attention to any information or side-effects that may be relevant in your particular case. This leaflet has been produced, funded and independently verified by Arthritis Research UK. Arthritis Research UK Copeman House, St Mary s Court, St Mary s Gate, Chesterfield, Derbyshire S41 7TD Tel 0300 790 0400 calls charged at standard rate Registered Charity No 207711 Arthritis Research UK 2011 Published September 2011 2258/D-PAIN/11-1 This paper is made up of 100% fibre ECF virgin wood fibre, independently certified in accordance with the FSC (Forest Stewardship Council). www.arthritisresearchuk.org